1. Field of the Invention
The present invention relates to a spinning-reel oscillating device. More specifically, the present invention relates to a spinning-reel oscillating device for oscillating a spool that is attached to a reel unit of a spinning reel front and rear in cooperation with handle rotation via a spool shaft.
2. Background Information
A spinning reel includes an oscillating mechanism (one example of spinning-reel oscillating device) for oscillating a spool front and rear in cooperation with handle rotation. With this type of oscillating mechanism, it is known to employ a reduction gear in which a slider is shifted by a rotary shaft, or a transverse cam system in which a slider is shifted by a threaded shaft arranged parallel to a spool axis.
With this type of reduction gear oscillating mechanism, the spool is axially oscillated by converting rotational movement into rectilinear movement. Accordingly, the speed of axial movement of the spool is much slower, thus, fishing line is prone to be wound onto the spool in an hourglass shape, whose ends expand, rather than in a cylindrical shape whose outer peripheral surface is parallel to a spool body. To address this issue, in order to wind fishing line in a shape closer to a cylindrical shape, it is conventionally known to axially oscillate a spool while suppressing variation of the speed of axial movement by combining two bi-lobe elliptic gears which are noncircular gears (see, for example, Japanese unexamined patent application publication 52-127887) among reduction gear oscillating mechanisms.
The above conventional oscillating mechanism includes a bi-lobe first elliptic gear, a rotary cam, and a slider. The first elliptic gear which is a non-circular gear is provided on a handle shaft. The rotary cam includes a second elliptic gear having teeth, the number of which is equal to that of the first elliptic gear. The second elliptic gear is arranged to mesh with the first elliptic gear such that their major axis lines come orthogonal to each other every time the second elliptic gear rotates 90°. The slider engages the rotary cam, and is axially shifted. A spool shaft is mounted to the slider so as to be immovable in the axial direction relative to the slider.
In the case that the conventional oscillating mechanism with this configuration is used, since mesh between the elliptic gears converts rotational movement of the handle into axial movement of the slider, the speed of axial movement of the spool does not vary too much relative to the rotation of the handle. As a result, the fishing line can be wound in a shape closer to a cylindrical shape.
With the above conventional configuration, the mesh between the two elliptic gears, which are orthogonal to each other, convert rotational movement of the handle into axial movement of the slider, thus the speed of axial movement of the spool does not vary too much relative to the rotation of the handle. However, since the two elliptic gears have the same number of teeth, the rotation speed of the handle is equal to the rotary cam. For this reason, the spool is axially oscillated in a relatively high speed, therefore, the fishing line cannot be tightly wound onto the spool.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved spinning reel oscillating device that overcomes the above described problems of the conventional art. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.